Folding mandrel for making bags



March 1954 T. JUN GMAYR FOLDING MANDREL FOR MAKING BAGS 3 Sheets-Sheet 1 Filed March 29, 1951 March 9-, 1954 T. JUNGMAYR 2,671,333

FOLDING MANDREL FOR MAKING BAGS Filed March 29, 1951 3 Sheets-Sheet 2 Theodof 3am n I! 2 l .I ll n I x.

March 9, 1954 Filed March 29, 1951 T. JUNGMAYR FOLDING MANDREL FOR MAKING BAGS 3 Sheets-Sheet 3 77 g Theodor3' n5 q" \NYENTOR- Patented Mar. 9, 1954 UNITED STATES PATENT OFFICE 2,671,383 FOLDING MANDREL FOR MAKING BAGS Theodor J ungmayr, Stuttgart, Germany,- assignor to Firma Fr. Hesser, Maschinenfabrik-Aktiengesellschaft, Stuttgart-Bad Cannstatt, Germany, a corporation of Germany Application March 29, 1951, Serial No. 218,127

Claims priority, application Germany May 16, 1950 4 Claims. (01. 93-12) This invention relates to certain improvements in machines for manufacturing packing envelopes or bags of paper or another suitable material, of the type in which the cut blank of the packing envelope is folded around a folding mandrel or core bar and glued.

More particularly, the invention relates to foldingeore bars of the type comprising two interconnected longitudinal halves which are relatively adjustable in order to be able to alter the cross section of the core bars for making packing envelopes of different widths.

one feature of my invention consists in that the fixing of one core bar half in relation to the other half is achieved by self-docking gear means forming part of the adjusting device.

According to a further feature of the invention, means are provided for permitting adjustment of the two longitudinal halves during movement of the core bar in case of machines in which the folding core bar is swingably or rotatably mounted.

A further feature of the invention consists in that in machines having a plurality of folding core bars the adjustment can be achieved by common adjusting means.

Other and further objects, features and advantages of the invention will be pointed out hereinafter and appearin the appended claims form ing' part of the application.

In the accompanying drawings several now preferred embodiments of the invention are shown by way of illustration and not by way of limitation.

Fig. l is an axial section of a folding core bar arrangement having the invention applied there to, in case of a machine provided, e. with 8 folding core bars,

Fig 2 is a plan view on the arrangement of Fig. l, the upper part of the upper longitudinal half of the foldin core bar being omitted,

Fig. 3 is a cross section on line A43 of Fig. 1,

Fig. 4 is a vertical section of another embodiment of the invention, for common adjustment of the cross section of all folding core bars, to gether with the device for carrying out this com mon adjustment,

Fig. 5 is a plan view of Fig. 4, the upper longitudinal half of the core bars being omitted in case of some of the core bars and the lower longitudinal half being shown in a horizontal section in case of one core bar,

Fig. 6 is aside view, on a larger scale, partl in section, of another embodiment of the device for simultaneous adjustment of the cross sec tion or all core bars.

5. 5 v or bolts 4 and s for vertical sliding in bores 38a Similar reference numerals denote similar parts in the different views.

In the embodiments illustrated the folding core bar consists of a fixed upper longitudinal part I and a lower longitudinal part 2 adapted to be adjusted parallelly thereto in a vertical direction. Fig. 1 shows an embodiment of the invention for the manufacture of packing envelopes provided with a larger number of folding core bars, e. g. 8 core bars. The machines of this type are generally known and therefore need not be shown and described in detail, since they do not form thesubject of the invention. It will be sulhcient to mention that the folding core bars are secured to the flange 32 of ahub l8 fastened in its turn on a vertical shaft 20. This shaft, as will be seen for instance from Fig. 4, is mounted for rotation in a bearing 22 of the machine table 24 and can be rotated either intermittently or continuously by a driving device of conventional type. At one station of the machine is arranged a folding case 26 which can be vertically reoiprocatedby a rod 28 guided in the bearing 21 of the table 24 and on to which the blank Z serving for formation of the packing envelope is fed also in per se known manner. As known in the art, the blank is folded U-fashion around the folding core bar 2, by an upward motion of the folding case 26. On further stations passed by the folding core bar during its travel the parts of the blank upwardly projecting from the folding core bar are folded on to the upper side of the folding core bar and pasted together", and the hose thus formed is then closed and pasted up at the front end of the folding core car, also in a manner as known in the art. These operations and the means serving for carrying them out arewell known in the art and do not form the subject of this invention, so that no special description and illustration will be required in this respect.

In the particular exemplification as per Figs. 1 to 3 the lower longitudinal part of the folding core bar consists of a plate 2 which is vertically slidable in the upper longitudinal half I of the folding core bar. The upper longitudinal half I in turn consists of an upper part la and a lower art it jolnted to the upper part la by means of a pin 239. Theupper part la of each folding core bar is secured by screws 39 on the flange 32 of the hub I8. In this case the lower parts lb of the folding core bars have surfaces 34 for engagemer t of corresponding surfaces 36 of shaft 20.

The plate 2 forming the lower longitudinal half of the folding core bar is guided by means of pins and 38b of inner projections 40a and 40b of the lower part lb of the upper longitudinal half I. The upper parts of the bolts 4 and 6 are provided with threads 8a and 81) for threadable engagement with nuts 42!]. and 4217 which are rotatable but not axially shiftable in caps 44a and 44b secured on the projections 40a and 40b. Said units are provided at their circumference with a worm gear toothing engaging worms 46a and 46b fastened on a spindle I2 rotatably mounted in bearing projections 48a and 48b of the part Ib but secured against longitudinal sliding by rings 50a, 50b fastened thereon. The outer end of the spindle I2 is provided with a head 52 embedded in a corresponding recess of the part Ib, so as to be flush with the front wall of the core bar, and provided with a recess 54 for engagement of a suitable key for rotation of the spindle I2. It will be seen from the foregoing that by rotating the spindle I2 the plate 2 forming the lower longitudinal half 2 of the folding core bar can be vertically adjusted in relation to the upper part I of the core bar and parallelly thereto. The fixing of the cross section adjusted is achieved by the self-locking effect of the gears 42a, 46a and 42b, 4612.

In the embodiment as per Figs. 4.- and the upper longitudinal halves I of the folding core bars are fastened by screws 38 on the longitudinal flange 32 of the hub I8, in the same way as in the aforedescribed embodiment as per Figs. 1 to 3. The lower halves 2 of the core bars on the contrary are swingably mounted, by means of pins 60, on arms 3! arranged star-fashion on a sleeve 58 slidable on shaft 26, engaging by means of plane surfaces 35 of their inner ends corresponding plane surfaces of the sleeve 58. Thus, by vertically shifting the sleeve it is possible to shift or adjust all lower halves 2 of the core bars jointly in relation to the upper halves I thereof and thus to change the cross-section of all folding core bars simultaneously. In the exemplification illustrated the sliding adjustment of the sleeve 58 is achieved by a cross bar 69 passing through a hole at the lower end of a rod 62 and being secured with its ends in holes of the sleeve 58. The cross bar 60 may be vertically shifted in a slot 64 of shaft 20 by the rod 52 which is slidable in a central bore of shaft 20, but owing to the cross bar 60 is not rotatable, and is threaded at its upper end Bl protruding over the upper tapered end 56 of the shaft 20, for engagement with a nut 68 toothed at its circumference. Fastened to the upper end 68 of shaft 20 is a sleeve Ii! embracing by a ring-shaped recess I2 a fiange shaped projection Id of the sleeve 68, so that the nut 68 can be rotated but is prevented from longitudinal sliding.

In the embodiment illustrated the unit 68 is rotated by a spindle I4 provided at its inner end with a bevel wheel 18 and at its outer end with a hand wheel T6. The spindle I4 is mounted for rotation and longitudinal sliding in a bearing 8P. of a bracket 82 mounted on the table 2 1 and in the bearing 84 of a bracket 86 mounted on a bracket 88 of the table 24.

The spindle I4 is normally in the position as shown by dot and dash lines in Fig. 4, at (1B) for bevel wheel 18 and at (1B) for hand wheel IS, in which position bevel wheel I8 is out of engagement with the toothing of the nut 68. In order to adjust the lower halves 2 of the core bars the bevel wheel I8 is engaged with the toothing of the nut 68 by longitudinal shifting of spindle I4. By rotation of the hand wheel It the nut 63 is 4 also rotated, whereby the rod 62 is shifted in the shaft 20. The rod 62 transmits the shifting motion through the transverse bar 60 to the sleeve 58 and thus to all lower halves 2 of the core bars so that depending on the direction and amount of rotation of the spindle I4 the lower halves 2 of the core bars can be adjusted simultaneously in relation to the upper halves I thereof. In order to prevent the lower halves 2 of the core bars from lateral rotational displacement in relation to the upper core bars, the sleeve 58 is connected to the upper halves I of the core bars by slidably arranged pins 90. In this embodiment the fixing of the cross section adjusted is achieved by the self-locking effect of the gear. The common shifting of the lower halves 2 of the core bars can also be effected during operation of the machine, so that a guidance and easy adjustment of the cross section of the core bars can be achieved.

Fig. 6 shows on a larger scale a modified form of the device for shifting the rod 62, only the upper end of the shaft 20 being shown apart from rod 62. The shifting of the rod 62 in this case is achieved by a two-armed knee lever 92 hinged on pivots 94 in a bearing 96 of a bracket 98 mounted on the machine table 24. The horizontal arm of the knee lever 92 is bifurcated at its front end at 25 and the bifurcated part 25 by means of pins 3 engages in an annular groove 5 at the upper end of rod 62 so that the same is permitted to rotate freely in the bifurcated end 25 of the arm of the knee lever 92. The lower end of the vertical arm of the knee lever 92 is also bifurcated at i and engages, by pins 9 of the bifurcated end I, a nut II seated on the threaded end iii of a spindle I'l, mounted for rotation but secured against shifting in a bearing I9 of a bracket 93 and provided at its extreme end with a hand wheel 2| so that by rotation of the hand wheel 2i through nut II and knee lever 92 the rod 52 can be shifted within shaft 20 in either direction for simultaneous adjustment of the lower longitudinal halves of all folding core bars, in the manner as shown in, and described with reference to, Figs. 4 and 5.

While the invention has been described in detail with respect to certain now preferred examples and embodiments of the invention it will be understood by those skilled in the art after understanding the invention that various changes and modifications may be made without departing from the spirit and scope of the invention and it is intended, therefore, to cover all such changes and modifications in the appended claims.

What is claimed is:

1. A folding mandrel arrangement for making packing bags, comprising in combination, a rotatable shaft, a plurality of folding mandrels each comprising two longitudinal halves one of which is fixed on said shaft, a common sleeve slidably mounted on said shaft and carrying the other halves, and means for adjusting the sleeve and fixing it in any adjusted position corresponding to a desired cross-section of the folding mandrels.

2. A folding mandrel arrangement for making packing bags, comprising in combination, a rotatable shaft, a plurality of folding mandrels each comprising two longitudinal halves one of which is fixed radially on said shaft, a common sleeve slidably mounted on said shaft and carrying the other halves, a rod shiftably mounted within a central bore of the shaft, means for connecting said rod to the sleeve, 2. male thread on the end of the rod projecting from the shaft, a nut rotatably but non-shiftably mounted on the upper end of the shaft and engaging said male thread, and means for rotating said nut, for simultaneously adjusting the sleeve and fixing it in any adjusted position corresponding to a desired cross-section of all folding mandrels.

3. A folding mandrel arrangement for making, packing bags, comprising in combination, a re--v volvable shaft, a plurality of folding mandrels each comprising two longitudinal halves one of which is fixed radially on the shaft, a common sleeve slidably mounted on the shaft and carrying the other halves, a rod shiftably mounted within a central bore of the shaft, a cross bar connecting said rod to the sleeve, through a longitudinal slot of the shaft, a male thread on the end of the rod projecting from the shaft, a nut rotatably but non-shiftably mounted on the upper end of the shaft and engaging said male thread, and means for rotating said nut, for simultaneously adjusting the sleeve and fixing it in any adjusted position corresponding to a desired cross-section of all folding mandrels.

4. A folding mandrel arrangement for making packing bags, comprising in combination, a revolvable shaft, a plurality of folding mandrels each comprising two longitudinal halves one of which is fixed radially on the shaft, 2. common sleeve slidably mounted on the shaft and carrying the other halves, a rod shiftably mounted within a central bore of the shaft, means for connecting said rod to the sleeve, a knee lever whose one arm engages rotatably but non shiftably an annular groove in the upper end of the rod projecting from the shaft, a nut mounted on the other arm of the knee lever, and means including a threaded spindle engaging said nut, for adjusting the angular position of the knee lever, for adjusting the sleeve and fixing it in any adjusted position corresponding to a desired cross-section of all folding mandrels.

THEODOR JUNGMAYR.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 704,807 Kellner July 15, 1902 863,180 Howard Aug. 13, 1907 977,222 Roberts Nov. 29, 1910 1,530,003 Larson Mar. 1'7, 1925 1,837,887 Schmidt Dec. 22, 1931 1,896,219 Buckley Feb. 7, 1933 2,257,689 J ungmayr Sept. 30, 1941 FOREIGN PATENTS Number Country Date 24,402 Australia of 1929 252,100 Germany of 1912 478,518 Germany of 1929 

